Apparatus and method for carrying out reactions in a fluidized bed

Apparatus comprising a rotatable drum having a circumferentially extending wall which is permeable to gases, feed means for mixing a gaseous fuel and a gaseous oxidant and for feeding the mixture through the wall into the drum, a bed of particles, which, at least when the apparatus is in use, is supported on an internal face of the peripheral wall and is fluidised, whereby the fuel is burned in the bed, and a reservior containing a mass of further particles, the reservoir being arranged for discharge of the further particles into the bed and means being provided for controlling the dishcarge of particles from the reservoir into the bed.

Apparatus comprising a rotatable drum having a circumferentially extending wall which is permeable to gases, feed means for mixing a gaseous fuel and a gaseous oxidant and for feeding the mixture through the wall into the drum, a bed of particles which, at least when the apparatus is in use, is supported on an internal face of the peripheral wall and is fluidised, whereby the fuel is burned in the bed, means defining a passage through which fluidising gas is fed to the circumferential wall of the drum when the apparatus is in use, one side boundary of the passage being defined by said circumferential wall, and a flame trap in said passage.

Apparatus comprising a rotatable drum having a circumferentially extending wall which is permeable to gases, feed means for mixing a gaseous fuel and a gaseous oxidant and for feeding the mixture through the wall into the drum, a bed of particles which, at least when the apparatus is in use, is supported on an internal face of the peripheral wall and is fluidised, whereby the fuel is burned in the bed, and variable speed drive means for rotating the drum, the drive means having adjustable speed control means whereby the speed of rotation of the drum can be varied selectively.

Apparatus comprising a rotatable drum having a circumferentially extending wall which is permeable to gases, feed means for mixing a gaseous fuel and a gaseous oxidant and for feeding the mixture through the wall into the drum, a bed of particles which, at least when the apparatus is in use, is supported on an internal face of the peripheral wall and is fluidised, whereby the fuel is burned in the bed, and a trap adjacent to an outlet opening of the drum for trapping particles which are carried out of the bed during operation of the apparatus.

Apparatus comprising a rotatable drum having a circumferentially extending wall which is permeable to gases, feed means for feeding a fluidising gas through the wall into the drum, a bed of particles which, at least when the apparatus is in use, is supported on an internal face of the peripheral wall and is fluidised by said gas and outlet means for receiving a solid or liquid reactant from outside the apparatus and delivering such reactant to the drum, whereby the fluidising gas and the reactant can react together in the bed.

Apparatus comprising a rotatable drum having a circumferentially extending wall which is permeable to gases, feed means for mixing a gaseous fuel and a gaseous oxidant and for feeding the mixture through the wall into the drum and a bed of particles which, at least when the apparatus is in use, is supported on an internal face of the peripheral wall and is fluidised, whereby the fuel is burned in the bed, wherein said wall defines a plurality of openings for admitting said mixture into the drum and said openings face in a tangential direction at the inner face of the wall.

A method of carrying out a chemical reaction in a fluidised bed wherein a drum having a permeable circumferentially extending wall is rotated, the bed is supported on the internal face of the wall, fluidising gas is admitted to the bed through the wall and the composition of the bed is varied in such a manner that the average size of the particles in the bed is ultimately greater than the average size of the particles in the bed initially.

A method of carrying out a combustion reaction in a fluidised bed wherein a drum having a permeable circumferentially extending wall is rotated, the bed is supported on the internal face of the wall, fluidising gas is admitted to the bed through the wall, the drum is initially rotated at a lower speed when the bed is cold and the drum is subsequently rotated at a higher speed when the bed is hot.

A method of treating a mixture comprising a gaseous oxidant and a combustible substance, the relative proportions being such that, if the mixture is ignited at ambient temperature, it will not continue to burn unless heat is transmitted to the mixture, in which method the mixture is fed through a permeable circumferentially-extending wall of a rotating drum into a bed of particles supported within the drum, the mixture being fed into the bed at a rate such that the bed is fluidised, and the mixture burns in the bed.